With the continuous development of the Internet technology, people can obtain more and more multimedia resources from the Internet, and watch movies or listen to music from the Internet. Accordingly, various audio and video software applications for the playback of multimedia files from the Internet have been developed. There is a need to further improve user experience and increase the functionalities of these applications.
Currently, each user terminal in the Internet can only independently control the playback of multimedia files. There has been no combination of multiple terminals for the control of the playback of a multimedia file. When watching a movie or listening to music, users can control the playback only using the terminal playing the movie or music. For example, when watching an online video clip or listening to online music using a software player installed on a personal computer (“PC”), in order to control the playback of the video clip or music, a user must input commands into the PC via the software player. This greatly limits the user's flexibility in controlling the playback.
In order to obtain better multimedia playback effect, a multimedia playback device, such as a desktop computer, a large-screen television (“TV”) or a home theater, typically has a large size and is not susceptible to frequent moves. In order to control the multimedia playback on such a device, a user must input commands into a control device, which is either a part of the playback device, or is connected with the playback device, through either wired or wireless connection. Examples of a control device being part of a playback device include buttons on a TV and the touch screen of a touch-screen PC, wherein users control the playback of multimedia files on the playback device by pressing the buttons or touching the touch screen. Examples of a control device connected to a playback device through wired connection include keyboard and mouse connected to a PC, wherein users control the playback of multimedia files on the PC by typing commands using the keyboard or clicking the mouse. Examples of a control device connected to a playback device through wireless connection include a remote control of a TV and wireless input devices of a PC such as wireless keyboard and wireless mouse connected to the PC wirelessly, such as via infrared or Bluetooth connection. While giving users the convenience of controlling playback from a distance, these wireless remote control devices have various disadvantages. For example, the functionalities of a TV remote control are limited by the buttons or keys on the remote control. Even if some of the keys are programmable, the resulting number of functions is still limited. Wireless keyboards and wireless mice can allow a user to take full advantage of all the functionalities of a PC. Their usefulness is limited in several respects, however. First, the wireless keyboard or mouse must be within a relatively short distance from the PC to which a receiver or adaptor is connected through wired connection in order to receive the control signal sent from the wireless device. In the case of infrared connection, there is the additional requirement that there is no block of the infrared beam between the wireless device and the receiver. Therefore, it is impossible, in the case of infrared connection, and almost impossible, in the case of Bluetooth connection, to control a PC outside the room in which the PC (and the receiver or adaptor) is located. Second, even though wireless keyboards and wireless mice allow a user to control a PC from a distance, the user still has to have visual contact with the PC's display in order to effect precise control, because all the control buttons are displayed in the PC's display and must be seen by the users in order to input any command to the PC. Even though it may be possible to effect the simplest playback control such as pause and stop using shortcut keys on a keyboard, most users do not memorize the shortcut keys. Even if they do memorize those shortcuts, in order to effect other controls, such as fast forward or selecting a file to play, visual contact with the PC's display must be established. These all make it impossible to control the playback from a distance far enough to reduce or eliminate the visibility of the PC's display. Third, none of the methods of control above is secure in that any person, having gained access to the control device, can control the playback using the control device. In other words, recognition and/or paring of a control device by the TV or PC is the only means by which the TV or PC can execute user commands sent from the control device.